Effects of lung collapse on pulmonary blood volume, flow and resistance

Pulmonary blood flow, pressures, volume and vascular resistance were measured when the lungs occupied an expiratory position in the closed chest and when they were collapsed by introducing air into the thorax. Circulation and innervation were intact. Variations due to respiratory movements or asphyxia were ruled out. Mongrel dogs were used, anesthetized with morphine and sodium pentobarbital. Pressures were measured from pulmonary artery, left atrium, aortic arch and intrapleural space. Pulmonary flow was evaluated utilizing the dye dilution method and the pulse contour method. Vascular volume was estimated by the product of mean circulation time and flow. When the lungs were collapsed there was an immediate elevation of intraluminal left atrial pressure but not a comparable rise in pulmonary arterial pressure. However, the direct records of arteriovenous pressure drop suggest that there was a delayed rise in pulmonary artery pressure. Flow, aortic pressure, heart rate and pulmonary vascular resistance showed no consistent changes. In 8 of 11 cases the pulmonary blood volume decreased when the lungs were collapsed.

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Effects of serotonin on pulmonary blood volume in the dog

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1962.202.5.957 ◽

1962 ◽

Vol 202 (5) ◽

pp. 957-960 ◽

Cited By ~ 12

Author(s):

Charles J. McGaff ◽

William R. Milnor

Keyword(s):

Cardiac Output ◽

Blood Volume ◽

Vascular Resistance ◽

Transit Time ◽

Mean Transit Time ◽

Dilution Method ◽

Continuous Intravenous Infusion ◽

Pulmonary Blood Volume ◽

Control Value ◽

Vascular Bed

Changes in pulmonary blood volume produced by continuous intravenous infusion of serotonin (5-hydroxytryptamine) were measured in 16 experiments on ten dogs. Pulmonary mean transit time was measured by the dye dilution method, using consecutive injections into pulmonary artery and left atrium; pulmonary blood volume was calculated by multiplying this mean transit time by the cardiac output. Serotonin lowered pulmonary blood volume by an average of 2.9 ml/kg, or 26% of the control value ( P <0.001). Pulmonary vascular resistance increased 94 ru (resistance units) kg, and systemic vascular resistance fell 294 ru kg, effects similar to those reported by other investigators. The magnitude of the decrease in pulmonary blood volume indicates that a relatively large part of the pulmonary vascular bed is constricted by serotonin, and provides an example of shifting of blood from pulmonic to systemic circuits by reciprocal changes in the distensibility of these beds.

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Experimental evaluation of a pulse contour method for calculation of cardiac output

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1962.202.4.622 ◽

1962 ◽

Vol 202 (4) ◽

pp. 622-630 ◽

Cited By ~ 4

Author(s):

Eugene F. Bernstein ◽

Robert L. Evans

Keyword(s):

Cardiac Output ◽

Pressure Change ◽

Pulse Contour ◽

Contour Method ◽

Dilution Method ◽

Velocity Change ◽

Simultaneous Comparisons ◽

Pulse Contour Method ◽

The Relationship ◽

Better Than

A method of estimating cardiac output which depends on the analysis of a single propagated pressure wave and the relationship between pressure change and velocity change: Δ p = ρ c0 Δ v, has been evaluated experimentally in 84 almost simultaneous comparisons with dye dilution method measurements and 22 almost simultaneous comparisons with direct Fick measurements. A deviation of 13.4 ± 22.9% between the dye and pulse contour measurements was observed. In comparison with direct Fick measurements, the deviation was 19.1 ± 33.0%. The ability of this pulse contour method to follow changes in cardiac output was better than its ability to estimate absolute output, as indicated by these deviations. The usefulness of this pulse contour technique in estimating cardiac output in clinical and laboratory situations, with a beat-to-beat indication of changes in output, is discussed. In general, this method appears to have a useful degree of accuracy and offers a relatively simple approach to an important problem.

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THE ACCURACY OF THE CONTINUOUS CARDIAC OUTPUT MEASUREMENT BY THE PULSE CONTOUR METHOD UNDER CHANGES IN SYSTEMIC VASCULAR RESISTANCE

Anesthesiology ◽

10.1097/00000542-199109001-00456 ◽

1991 ◽

Vol 75 (3) ◽

pp. A457-A457 ◽

Cited By ~ 4

Author(s):

M. Specht ◽

Chr. Apenburg ◽

K. Wichmann ◽

K. Reinhart

Keyword(s):

Cardiac Output ◽

Systemic Vascular Resistance ◽

Vascular Resistance ◽

Pulse Contour ◽

Cardiac Output Measurement ◽

Continuous Cardiac Output ◽

Contour Method ◽

Output Measurement ◽

Pulse Contour Method

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An Uncalibrated Pulse Contour Method to Measure Cardiac Output During Aortic Counterpulsation

Anesthesia & Analgesia ◽

10.1213/ane.0b013e318230b2de ◽

2011 ◽

Vol 113 (6) ◽

pp. 1389-1395 ◽

Cited By ~ 21

Author(s):

Sabino Scolletta ◽

Federico Franchi ◽

Fabio Silvio Taccone ◽

Katia Donadello ◽

Bonizella Biagioli ◽

...

Keyword(s):

Cardiac Output ◽

Pulse Contour ◽

Contour Method ◽

Pulse Contour Method

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Evaluation of slope method for measuring pulmonary blood volume in man

Journal of Applied Physiology ◽

10.1152/jappl.1962.17.3.497 ◽

1962 ◽

Vol 17 (3) ◽

pp. 497-502 ◽

Cited By ~ 3

Author(s):

Lockhart B. McGuire ◽

Donald S. Dock ◽

John W. Hyland ◽

Donald C. Harrison ◽

Florence W. Haynes ◽

...

Keyword(s):

Pulmonary Artery ◽

Blood Volume ◽

Transit Time ◽

Human Subjects ◽

Mean Transit Time ◽

Close Correlation ◽

Artery Occlusion ◽

Pulmonary Blood Volume ◽

Slope Method ◽

Predominant Effect

Knowledge of the pulmonary blood volume is important in several areas of circulatory physiology. However, adequate methods for measuring this volume have not been established. The slope of an indicator-dilution curve across the central circulation has been used in several studies as an indication of this volume. In the present study the blood volume between pulmonary artery and left atrium was measured in 31 human subjects by an application of the well-established mean transit time principle. Slope volumes were also measured. There was poor agreement between the results of the two techniques. Unilateral pulmonary artery occlusion consistently reduced pulmonary blood volume by the mean transit time method, with only minor and less consistent changes in slope volumes. A close correlation between the slopes of curves from simultaneous pulmonary artery and left atrial injections suggested a predominant effect on both curves of factors at or distal to the left side of the heart. It was concluded that the slope method did not measure the pulmonary blood volume in man. Submitted on June 8, 1961

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Comparison of estimation of cardiac output using an uncalibrated pulse contour method and echocardiography during veno-venous extracorporeal membrane oxygenation

Perfusion ◽

10.1177/0267659119883204 ◽

2019 ◽

Vol 35 (5) ◽

pp. 397-401

Author(s):

Ottavia Bond ◽

Selene Pozzebon ◽

Federico Franchi ◽

Federica Zama Cavicchi ◽

Jacques Creteur ◽

...

Keyword(s):

Blood Flow ◽

Cardiac Output ◽

Extracorporeal Membrane Oxygenation ◽

Linear Regression Analysis ◽

Pulse Contour ◽

Contour Method ◽

Cardiac Output Monitoring ◽

Membrane Oxygenation ◽

Output Monitoring ◽

Pulse Contour Method

Introduction: During veno-venous extracorporeal membrane oxygenation, cardiac output monitoring is essential to assess tissue oxygen delivery. Adequate arterial oxygenation depends on the ratio between the extracorporeal pump blood flow and the cardiac output. The aim of this study was to compare estimates of cardiac output and blood flow/cardiac output ratios made using an uncalibrated pulse contour method with those made using echocardiography in patients treated with veno-venous extracorporeal membrane oxygenation. Methods: Cardiac output was estimated simultaneously using a pulse contour method (MostCareUp; Vygon, Encouen, France) and echocardiography in 17 hemodynamically stable patients treated with veno-venous extracorporeal membrane oxygenation. Comparisons were made using Bland–Altman and linear regression analysis. Results: There were significant correlations between cardiac output estimated using pulse contour method and echocardiography and between blood flow/cardiac output estimated using pulse contour method and blood flow/cardiac output estimated using echocardiography (r = 0.84, p < 0.001 and r = 0.87, p < 0.001, respectively). Bland–Altman analysis showed a good agreement (bias −0.20 ± 0.50 L/min) and a low percentage of error (25%) for the cardiac output values estimated by the two methods. The bias between the blood flow/cardiac output ratios obtained with the two methods was 5.19% ± 12.3% (percentage of error = 28.1%). Conclusions: The pulse contour method is a valuable alternative to echocardiography for the assessment of cardiac output and the blood flow/cardiac output ratio in patients treated with veno-venous extracorporeal membrane oxygenation.

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